Soft-Start LED Driver using RC Time Constant & BJT

Overview : This project implements a Soft-Start LED Driver designed to transition an LED from "off" to full brightness gradually. By combining an RC charging circuit with an NPN transistor, we eliminated the abrupt power-on flash, creating a smooth visual fade-in effect. ---------- Circuit Components : - 1x NPN Transistor: Acts as the current controller. - 1x Red LED: The visual output. - 3x 100µF Capacitors: Connected in parallel (Total 300µF) to extend the start-up time. - Resistors: 330Ω (LED protection) and 2x 50kΩ (Timing and Base control). - Power: 9V DC Battery. ---------- How it Works : The circuit relies on the RC Time Constant (tau = R x C). When powered, the parallel capacitors charge through the 50kΩ resistor, slowly increasing the voltage at the transistor's base. This gradual rise in base current allows the transistor to slowly increase the current flowing through the LED until it reaches full illumination.